The invention relates to a vehicle pane with at least one heating conductor and at least one antenna.
WO 2007/023054 relates to an antenna system, in particular for a vehicle pane with a heating conductor field, in particular on or in a vehicle pane, and with an antenna conductor structure, which is coupled to the heating conductor field using high frequency technology. Furthermore, this prior art describes a multi-range antenna system that is intended, in particular, for a vehicle pane and exhibits the following features: a heating conductor field having lateral recesses, in particular, on or in a vehicle pane, an antenna conductor structure for at least two reception ranges outside the heating conductor field, which is arranged essentially in the lateral recesses of the heating conductor field, and a low resistance, but non-electric coupling of the antenna conductor structure to the heating conductor field using high frequency technology.
This known antenna conductor structure is effective for one of the at least two reception ranges. The heating conductor field is configured so as to form two parts with a large heating conductor field area, which covers the pane from the left edge of the vehicle pane as far as to the right edge of the vehicle pane and from a bottom edge upwards to almost an apex of a wiping field, which is covered when the windshield wiper is operating. An upper peak area of the wiping field has a small heating conductor area, which does not extend laterally as far as the edge of the vehicle pane and extends upwards just barely beyond the wiping field. Both heating conductor field areas have a rectangular basic shape, on which the heating conductors run horizontally in a straight line. Both heating conductor areas are supplied by common bus bars, where the bus bars are mounted on a left edge and/or on a right edge of the respective heating conductor area in corresponding bus bar sections.
A drawback with the above design is that the bus bar sections that relate to the various heating conductor field areas, as well as the feed lines to the bus bars, have to be designed so as to vary in width and/or thickness in order to be able to send an approximately identical current through all of the heating conductors. However, the different conductor thicknesses are visually easy to detect, a feature that produces a non-uniform and low quality appearance. Furthermore, the right and the left bus bar remain on the opposite pane sides, as a result of which the open spaces or the free areas that are used for mounting the antenna structure are comparatively small.
The object of the invention is to avoid the afore-mentioned drawbacks and to provide, in particular, a vehicle pane, which makes possible an improved antenna function.
This object is achieved according to the invention by a vehicle pane that exhibits a heating conductor field with at least one heating conductor and at least one antenna, wherein the at least one antenna is mounted on an area of the vehicle pane that is free with respect to the heating conductor field and wherein the heating conductor field has the basic shape of an essentially angular sector.
Since the heating conductor field has the basic shape of an essentially angular sector, it is possible, in contrast to, for example, a rectangular heating conductor field, for the side of the free area of open space to be significantly enlarged, a feature that in turn allows greater design flexibility for antennas that are mounted on the open space. The open space is typically not heated. The heating conductor field can be defined, for example, in essence by an outer contour of at least one heating conductor structure. The basic shape of an angular sector can include the basic shape of a circular sector or the basic shape of an annular sector.
The significantly enlarged open space makes possible the further development that the vehicle pane has two or more antennas, each of which is mounted on a different area of the free area of the vehicle pane. In this way it is possible to adapt to the different boundary conditions (frequency ranges, etc.) with a different lay-out of the antennas, a feature that in turn makes it possible to improve the reception. The two antennas can differ not only in their construction but also in their function. As an alternative, one antenna can be mounted on a plurality of open spaces or open space areas in order to achieve a better performance.
In particular, it is a further development that one of the antennas mounted on (that is, on or in) the free area is used for an AM reception (AM antenna), whereas the other antenna is configured for other functions, like FM reception, DAB, radio remote control services and/or TV. As an alternative, an AM antenna, etc. may be mounted on and/or distributed over a plurality of open spaces or open space areas in order to achieve an enhanced performance.
An additional further development and also autonomous solution to the technical problem is that the vehicle pane, which exhibits a heating conductor field with at least one heating conductor and at least one antenna, the at least one antenna being mounted on an area of the vehicle pane that is free with respect to the heating conductor field, has bus bars for supplying power to at least one heating conductor. The bus bars are arranged on a common or identical edge and/or side area of the vehicle pane and/or are concentrated on one side of the pane. This positioning of the bus bars allows for an especially compact heating conductor field and, thus, especially large open spaces, because the heating conductor field does not have to be run over the vehicle pane between two bus bars that are arranged on opposite edges.
Especially for vehicles, which have a hatchback that is provided with the vehicle pane, it is a further development that the bus bars are arranged on either the bottom edge or on the upper edge, as a function of whether the windshield wiper is positioned on the bottom edge and/or the side area or on the upper edge and/or the side area of the vehicle pane. This configuration offers the advantage of greater robustness in the electromagnetic coupling, because in the past, for example, as shown in WO 2007/023054, the cable harnesses in hatchback vehicles ran right and left parallel to the right and left side panes. In these locations were also the bus bars, as a result of which it is possible to achieve a very good, but undesired coupling between the respective cable harness and the rear pane antenna, a feature that can easily result in interference. In contrast, the present configuration can reduce the coupling, because the at least one antenna that is mounted on the open space can be designed such that it has only a few connections that run parallel to the right and/or left edge of the pane.
It is also a further development that at least one section of the at least one heating conductor is designed as an arc shaped heating conductor section that runs between the bus bars. The at least one arc shaped heating conductor section can be designed so as to be curved or arced. Then, the resulting heating conductor field can have the shape of either an annular sector or a circular sector. The roundness of the antenna permits a far better vertical polarization than is the case with the conventional pane antennas.
As an alternative, the at least one arc shaped heating conductor section can be designed in such a way that it has a plurality of straight subsections, where the adjacent subsections are angled in relation to each other. Such a polyline-like arc shaped heating conductor section can have, for example, three straight subsections that form a U shape so that the legs are sloped outwards. Then the resulting heating conductor field can exhibit the shape of a symmetrical trapezoid.
In a further development, the bus bars are arranged in a black print area. As a result, the bus bar can be hidden from the sight of a viewer, a feature that produces a visually high quality appearance.
Yet another further development consists of configuring or providing at least one antenna in order to operate at least in the AM range. In principle, one or more antennas or antenna structures can be configured to operate at least in the AM range and/or can be operated at least in the AM range. The at least one antenna can be configured and/or provided exclusively for AM operation or for a mixed operation in the AM range and in at least one other range, for example, for FM or DAB reception, etc.
According to an additional further development, at least two (totally curved or polyline-like) arc shaped heating conductor sections are electrically connected together in series. This measure allows a length adaptation of the heating conductor between the bus bars to be achieved, a feature that makes possible a width adaptation of the heating conductor. The width adaptation of the heating conductor in turn results in a heating conductor field that is inconspicuous from a design viewpoint.
A subsequent further development lies in the fact that the vehicle pane has a group of several, for example, at least four, preferably adjacent, arc shaped heating conductor sections so that pairs of the arc shaped heating conductor sections are electrically connected together in series alternatingly from the outside inwards. As a result, it is possible to achieve an especially good length adaptation in a simple way.
One configuration is that a common length of the arc shaped heating conductor sections that are connected together in series lies inside a predefined area. For this purpose three or more arc shaped heating conductor sections can also be connected together in series.
In a subsequent design the vehicle pane has arc shaped heating conductor sections that are connected together in series and arc shaped heating conductor sections that are not connected together in series. Hence, a common length of both the arc shaped heating conductor sections that are connected together in series and the arc shaped heating conductor sections that are not connected together in series lies inside a predefined area.
In another embodiment, the at least one heating conductor is configured at least partially as an antenna. In this case the heating conductor antenna is used preferably for a reception of FM, DAB, TV, etc. For this purpose the heating conductor antenna is suitably wired using electrical technology, for example, with inductances in the heating conductor field terminals.
In an additional design, the vehicle pane has a plurality of antenna terminals, where all of the antenna terminals are concentrated in a narrow area. Then, the antenna terminals can be housed in a common compact housing, optionally together with the associated antenna amplifiers or parts thereof. As an alternative or in addition, the antenna amplifiers or parts thereof can also be arranged at a distance from the rear pane, for example, on a structure of the vehicle body.
Furthermore, it is a further development that the antenna terminals and/or the housing are arranged in a black print area. As a result, these components can be hidden from the viewer's sight, a feature that produces a visually high quality appearance.
The amplifier housing may also be mounted centrally on an upper edge of the vehicle pane, a feature that enables an especially compact design with negligible wiring complexity. The at least one antenna that is mounted in an open space may be a log periodic antenna. As a result, the wideband capability of the antenna is increased.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.